Yes, I attended AOS interview. Before the pandemic, everybody was required to go through interview to get GC.
Right now this can happen for multiple reasons: either your case is weaker, or you were randomly selected. It's just like security at an airport, sometimes you have to go through additional scanning.
Good luck, make sure to prepare for the interview well, know your case, know your spouse and practice answering questions with the spouse.
It's rather a good sign that your case is moving.